Step-by-step explanation:
Let's say b is the rate of the boat in still water, and c is the rate of the current.
Distance = rate × time
Going upstream:
100 = (b − c) (5)
20 = b − c
Going downstream:
100 = (b + c) (2)
50 = b + c
Solve the system of equations using substitution or elimination. Using elimination, add the equations together:
70 = 2b
b = 35
c = 15
The boat's speed is 35 km/h, and the current's speed is 15 km/h.
Answer:
632.4
Step-by-step explanation:
Answer:
One standard deviation above the mean means a z-score of 1.0. If we put this into the calculator as normalcdf(1,999) = .159
15.9 percent of the athletes would have a distance greater than 20.56 meters.
Now multiply the number of athletes by the percent.
.159 * 40 = 6.346 = about 6 athletes
c. about 6 athletes
Step-by-step explanation:
the average rate of change between two input values is the total change of the function values (output values) divided by the change in the input values.
so,
(h(7) - (h(3)) / (7 - 3)
h(7) = 7² - 7×7 + 6 = 49 - 49 + 6 = 6
h(3) = 3² - 7×3 + 6 = 9 - 21 + 6 = -6
7 - 3 = 4
(6 - -6)/4 = 12/4 = 3
the average change rate in that interval is 3 (or fully 3/1).
